Storing Carbon in the Ocean

As carbon dioxide levels in the atmosphere continue to rise, it may be that clean energy technologies, electric cars, and other methods of reducing emissions may not be enough.  Carbon sequestration – sucking carbon out of the atmosphere – is seen by many as a crucial part of the solution.

There are many carbon capture and storage projects in development around the world in places ranging from Abu Dhabi to Norway.  But critics of the technology claim that it is just too expensive to do at the levels needed to be effective.

One approach that is often discussed is storing carbon in the world’s oceans.  The idea is not just to dump captured carbon into the sea.  One would have to manage it carefully.  Ten years ago, Harvard and Columbia researchers suggested that carbon dioxide could be pumped hundreds of yards into the sea floor at great ocean depths where low temperatures and high pressures would prevent it from going anywhere.  On paper it looked good, but large-scale implementation seems daunting at best.

Recently, scientists at the California Institute of Technology and the University of Southern California have developed a carbon sequestration technique using an enzyme that quickly helps CO2 turn into calcite.  Calcite is found in shellfish, plankton and the exoskeletons of coral in the ocean.

The idea is to speed up the natural chemical processes in which carbon dioxide is sequestered in the ocean, in this case by a factor of 500.   Whether this could work on a large scale and whether it wouldn’t cause other problems like adding to ocean acidification is not clear.  But novel ideas like this may be what is needed to tame the rising levels of CO2 in the atmosphere.

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Speed Up Oceanic Carbon Sequestration, to Fight Climate Change

Photo, posted December 1, 2007, courtesy of Tony Webster via Flickr.

‘Storing Carbon in the Ocean’ from Earth Wise is a production of WAMC Northeast Public Radio.